Fluorinated internal olefins and their preparation



1 i 1 a t'ni iiiii 7., FLUORINATEDINTERNAL OLEFINS Join: J. Drysdale wilmington, ne1.,'assi n6r to; t. 1; .11..

Pont de Nemours andCom any, Wilmington, Del., a

wrwt tm. 9 D w i: No Drawing Applicatr imitates a seriallqmflflfldz j l g 16 cum-453.3

invention relates to I highly fluorinated organic compounds.

Qdeveloped under reaction conditions or it can be carried out under reflux conditions at atmospheric pressure.

"theembodiment of this invention where-the reaction is carriedqout'in a closed system, the process-is conven- 5 'iently carried out by placing in a reaction vessel capable More particularly,'it relates to highly fluorinated olefinsand to a haethod for theirpreparation. l; Some fluorinated olefinshaving'thetethylenicdouble bond in the 1- or 2-position, i.e., -where' the ethylenic double bond is between the first and second, or between .the second and third carbons of; the olefin, and methods of withstanding the pressure developed by the reaction mixture under the operating conditions a fiuoroacyl halide y thefgeneralfformula given above or amixture' of such fiuaroac r halides -'and at least onelequivalent .of nickel carbon l and" thenheating' the reaction mixture at 100 W 200 0., preferably at l25 -175 C.

Reaction times are not .critical, at autogenous pressuse times ranging from ,4 hoursor less to 16 hours or mor being:satisfactory.5 In general, the longertimes otifreaction are employed when the lower operating temperatures in the above specified ranges are used; Atte r ;reaction; is completed, as evidenced by no further. pressure increase, the reactor and reaction mlxture are Ic ooledgthe pressure in the reactor isreleased, and the for preparing them are k nown; However, a general method for tm aking highly fluorinatedsinternal olefins in which'the' ethylenic bond is; on a carbon more than one carbon away from the terminal carbon of the olefin is not known. Inview of the potential interest in such fins and to provide a general-method of making the same. Pursuant to the above-mentioned and yet other objects, a general synthesis of highly fluorinated 'olefins I p p andis then -fracti internally unsaturated-fluoroolefins, objects pfthis in'ven- ,3; tion are, therefore, to provide a new class of such olereactor-isthen subjected, to reduced pressure to remove volatile compounds. The residual high boiling liquids and solids are removed fromthe reaction vessel and are added to an excessof'water,whereupon afl uorocarbon layer separates from the aqueous layer; The fluorocarbon layer is ;washed with aqueous sodium :carbonate 'onally. .distilledto isolate the fluoro- ;j-;In the tmospher c pressure embodirnent ot the process oi thi mventiom-gwhich is' preferred when, fiuoroacyl having the ethylenic bonds onlcarbonsgfotherthanlthe 7;1

,terminal carbons of theolefin, is now provided This novel synthesis comprises heating a'fluoroacyl halide of the formula p I BFaQX where R is any organic radical inert to nickel carbonyl, and, X is a halogen having, atomic number of at least 17, 'i.e., chlorine, bromine and iodine, with nickeljc'arbonyl. ata temperature between'40 and 200" C. An

especially'preferred embodiment of, theprocess of this invention comprisesheating a perfluoroacyl halide, an wahydroperfluoroacyl halide, ,or I an wrchloroperfluoroacyl halide of the general formula zwmnex wherein Z is hydrogen, fluorineo'r chlorine, nisian teger-between 2 and V, 20, inclusive; and XJischlorine,

bromine or iodine, with ni kel. carbonyl at atemper'avhalideslboilingabove 40 C. are employed, the reaction between the fluoroacyl halide, or mixture of fluoroacyl halides, and nickel carbonyl is carried out as follows:

'Ihefluoroacyl halide and the nickel carbonyl :are placed equation showing the. reaction of 7-hydroperfluorohepresistant;deter d n theifl o nated lefi The fluorinated internal olefins of the formulas .'The process of this invention can be carried out in a closed reaction system under thewvautogenous pressure the reaction vessel any n1 V through the water-cooled condens'erinto the coldtrap; After the reaction is completedpthe nickel chloride' precipitate fwhich forms is filtered from'the reaction mixture} I .dissolv edjin water. Any fluorocarbon that separates .iromthe'Yaque'ous nickel chloride solution iss'eparated' and combined withthe-filtrate from the reaction mixture.

a reaction vessel fitted with a water-cooled reflux condensentheoutletof which is connected to a trap cooled by solidfcarb'on dioxide inorde'r to collect any nickel carbonyl which' distills through the water-cooled condenser. Optionally, the reflux condenser can be cooled to about 20 C. and in this case a cold trapis not needed. The exit of the'cold trap is connected to a bubble tube to provide means for observing the rate of formation of carbon monoxide which passes through the'cold trap. v t

When high boiling fluoroacyl halides'are being employed, it is convenient to use an inert fluorocarbon, e.g., 1,-1,2-trichloro- 1,2,2 trifluoroethane as a solvent in order to lower the reflux temperature of the reaction mixture. The proportions of fluoroacyl halide and nickel carbonylfare not criticah-However, if it is desired to use up all-the fluoroacylhalide, it, is preferredtouse one mole, of

halide xqw, .7 'fI'he-lreaction, mixture is. heated to reflux vtemperature,

nickel carbonyl -for each mole offluoroacyl :des re a t e heat n an ba r p okr p The crude. vfluorocarbon reaction product is then'fractionallydistilled. to 'isolate the 'fluoroolefins that .are formed., The fluoroacyl halides used as starting materials in the, process oi invention can be made from the cor- 2,925,446. Pei ted Feb. 16, 1950 kel carbonyl thatdistills genating agents, e.g., thionyl chloride and phosphorus tribromide, or by reaction of the acyl chloride with caliodide. A 'detailed'description of they-preparation of polyfluoroalkanoic acids and theirconversion to acyl halides is given in U.S. Patents 2,559,629 and 2,559,630. The w-chloroperliuoroalkanoic acids can be prepared as responding fluoroalkanoic acids by treatment with halodescribed in US. Patent 2,790,815, and their conversion cuts are expressed in parts by weight-unless otherwise i specified. 7

Example I A stainless steel reaction vessel capable-of -withstand-.

ing high pressure is charged with 73 parts of'7 hydrope'r- V fluoroheptanoyl chloride and 34 parts-of nickel carbonyl and heated at 130 C. with agitation for 4*hours. The reaction vessel is then cooled,-evacuated with a vacuum pump to a pressure of approximately 1-2 mm. of mercury to remove the low boiling compounds, -'and the*residual high boiling liquids and solids are removed and agitated wtih 100 parts of water. The lower fluorocarbon layer which forms is separated from'the aqueousflayer and is washed with aqueous sodium carbonate solution and then distilled under reduced pressure. There is obtained a 50% conversion (7080% yield) of a mixture of 1,12 dihydroperfluoro 5 dodecene, 1,12 dihydroperfluoro-6-dodecene, and 1,1Z-dihydroperfluorododecane; boiling point 48-70 C./ 0.5 mm. Nuclear magneticresonance analyses of all fractions of this product are consistent with a mixture of the saturated and unsaturated fiuorocarbons.

Example II A stainless steel pressure vessel is charged with. 51 parts of nickel carbonyl and 69 partsof perfluorobutyryl chloride and heated at 150 C. with agitation for 8 hours. After cooling, the reaction mixture is pumped from the reaction vesselinto a trap chilled by a mixture of solid carbon dioxide and acetone and is then fractionally distilled at atmospheric pressure. The following fractions are obtained:

Nickel carbonyl codistiils with thereaction products in fractions l-7 and is removed by gas chromatography. Fractions 4 and 5 are a mixture of perfluo'ro-3-hexene, perfiudro-Z-hexene, and p-erliuorohexane. jFraction7 is principally perfluoro 4 heptanone. The structures of these products are assigned on the basis of nuclear magv netic resonance analyses and for fraction iby -itsgas chromatographic analysis.

Example III A stainless steel pressure vessel is charged with l3 f parts of l1hydroperfluoroundecanoyl chloride, "23 parts of perfiuorobutyryl chloride and 40 parts of'nickel care solution to destroy the ketone present.

.l hydroperfluorotridecanaboiling at. 82-96 ,C./10 mm,

amounting to 6 parts, corresponding to a yield of 40%. There is also obtained 2 parts (corresponding to a yield of 15%) of 1,20-dihydroperfluoro-10-eicosene, melting at 89-91 C. These products "are identified by nuclear magnetic resonance analyses'and the latter by elemental analysis. i

Analysis-(lewd for C ff gfl "C, 24.92%; H, 0.42%; F, 74.66%. ,Found: C, 25.25%; H, 0.67%; F, 74.31%. j, i i

' Example IV Using the reaction conditions described inExample III, 74- parts'of S-hydroperfluotovaleryl chloride and 51 parts of nickel carbonyl are reacted. There are isolated from the reaction mixture .1',8-dihydroperfluoro-4-octene, 1,8- dihydroperfiuoro 3 octene, 1,9 dihydroperfluoro 5- nonanone, and 1,8-dihydroperfluorooctane. These products ,areidentified by nuclear magnetic resonance analyses. v The procedure of Example IV is repeated 13 times and reaction products are combined. The combined reaction products are agitatedwithwater and the water-insoluble portion is then agitated with aqueous sodiurn'hydroxide The lower organiclayer is then distilled and there is obtained 125 parts of product boiling at 126-130 C. at atmospheric pressure. Nuclear magnetic resonance analyses show "this product is a mixture comprised of the octenes 1,8-

dihydroperfluoro-4octene and l,8-dihydroperfluoro-3- octene (80%) and 1,8-dihydroperfluorooctane (20%).

i Example V -.A reaction vessel fitted with a reflux condenser, the outlet of whichis connected in turn to a trap cooled by solid carbon dioxide and then to. a bubble tube, is charged with 90 parts of S-hydroperfluorovaleryl chloride and 40 parts of nickel carbonyl. 'The reaction mixtureis heated to reflux temperature (60 C.) whereupon carbon monoxide is evolved and nickel chloride precipitates.

Refluxing is continued for about one-half hour during which time the temperature of the reaction mixture reaches 80 C. The reaction vessel and its contents. are cooled to 25 C., the nickel carbonyl collected in the cold trap is replaced in the reaction vessel, and the heat- .ing cycle is repeated. After about 15 minutes at reflux corresponding .-to a 33% conversion and yield,'of

a mixture of ,1,8-dihydr,ope'rfluoro-3-octene and ,1,8-dihydroperfluoro-4-octene, boiling at 127-129 C. Nuclear magnetic resonance analysis indicates that these two fluoroolefinsare. present in approximately equal proportions. 4 Y

The examples have illustrated the process of'this invention by reference to reaction of nickel carbonyl with specific fluorinated acyl halides. However, the inventioniis generics-to the reaction of nickel carbonyl with any fiuoroacyl halide of theformula wherein R is any organic radical which is inert to nickel carbonyl and X is chlorine, bromine or iodine. Thus, when the fluoroacyl halides listed in the first column of the following table are reactedwith nickel carbonyl. under the conditions-defined hereinbefore, the specific internal fluoroolefins listed in the second column :ofthe ffollowing table-are obtained.

. 3-Hydroperfiuoropropionyl iodide;

Fluoroacyl Halide Reactant i Internal Fluoroolefin'Products 3-Hydroperfluoropropionyl chloid 1,4-Dlhydroperfluoro-2- butene. r e. Perfluorooctanoyl bromide Perfluoro-7-tetradecene and perfluoro-fi-betradecene.

1,40 Dihydroxyperfluoro 20 tetracontene and 1,40-dihydroxyperfluoro-lQ-tetracontene. V

1,4-Dihydroperfluoro-z-butene.

1,8-Dichloroperfluoro-i-octene and 1.S-dlehloroperfluoro-S-octene.

1,16-Dichloroperfluoro-S-hexedecene and 1,16-dichloropertluoro-7-hexadecene.

21-Hydroperfluorohenelcosanoyl chloride.

o-(lhloroperfiuorovaleryl chloride..-

Q-Ohloroperfluorononanyl chloride.

Perfluorosuccinyl fiuoro chlorlde hexenedlcarboxylle acid fluoride. Ferfluoro-d-octenedlcarboxylic acld' fluoride and perfluoro-3-octenedlcarboxylic acid fluoride. Perfluoro-5-decenedlcarb oxylic acid fluoride and perfluoro-t-decenedlcarboxyllc acidtluoride.

Perfluorogluteryl fiuoro chloride..-

Perfluoroadipyl fiuoro chloride..-

; I .The internal fluoroolefinsiof this invention are useful wherein x and y are integers between 1 and 19, in-- Perfluoro-3-hexenedicarboxyllc =acid fluoride and perfiuoro-2- Theembodimentsof the invention in which an exclusive property or privilege is claimed are defined as follows: 1

l. A fluorinated internal olefin of the group consisting of H(CF ),CF=CFC,F=, and

elusive.

. 1,l2-dihydroperfluoro-S-dodecene.

. 13-hydroperfluoro-3-tridecene.

. 13-hydroperfluoro-2-tridecene.

1,8-dihydroperfluoro-3-octene. v The process which comprises heating a fiuoroacyl halide of the formula RCFsCX wherein R is an organic radical inert to nickel carbonyl and X is halogen of an atomic number of at least 17, with nickel carbonyl at a. temperature of about 40-200" C.

8. The process of'claim 7 wherein R is perfluorinated and contains 1-19 carbons.

9. The process of claim 7 wherein R carries a member of the group consisting of hydrogen and chlorine on the carbon omega to the attached carbonyl group but is otherwise perfiuorinated and contains '1-19 scarbons.

as solvents for perfiuoroketones, perfiuoroacids, lowt melting polytetrafluoroethylene, and the'like. They are especiallyuseful as solvents for the polyfiuoro telomer alcohols described in US. Patent "2,559,628. For ex ample, the telomer alcohol oi formula V H(CF CF CH OH.

dissolved at a concentration of 5% in a warm mixture of 1,8 -'dihydroperfluoro- 3 octene, 1,8 dihydro perfluoro-4-octene, and l,S-dihydrdperfluorooctanc, pre pared as' described in Example IV. The resulting solu- I v '40 prepared from tetrafluoroethylene and methanol, can be p'e'ratmos'pheric pressure.

11. The process of claim 10 wherein thepressure autogenous,

' 12.. The .process]of-claim'7 accomplishedwith reflux ,at atmospheric pressure.

, 1:3. The process of heating 7-hydroperfluoroheptanoyl chloride with nickel carbonyl at 40-200 C.

14. The process of heating perfluorobutyryl chloride with nickel carbonylat'40-200" c. 7

tion can be applied to the surface of awood or metal 7 7 object and the solvent then evaporated to leave a layer of the solid telomer alcohol on the surface of the object as a lubricant.

The instant novel fluoroo efins are also useful as chemical intermediates. They can be oxidized,'for example, to form fluorocarboxylic acids useful in many applications. A specific illustration of this oxidation is thereaction of 1,8-dihydroperfluorbA-octene with potassium permanganate. When this fiuoroolefin is treated with an aqueous solution'of potassium permanganate at reflux temperature, it yields w-hydroperfluorobutyric acid.

Since obvious modifications "in the .invention' will be evident to those skilled in the chemical arts, I" propose to be bound solely by the appended'claims.

I 15. The process of heating ll-hydroperfluoroun I decanoyl chloride with nickel carbonyl at 40-200" C.

16. :The process 1 of heating S-hydroperfluorovaleryl chloride withnickelcarbonyl atf40-200 C.

References Cited in the file of this patent FOREIGN PATENTS 504,950 Canada Aug. 10, 1954' OTHER REFERENCES Henne et al.: Jour. Am. Chem. Soc., 73, 5527 '(1951).

Slesser et al.: Preparation, Properties, andTechnology of Fluorine and Organic Fluoro Compounds, page 837, 1951, McGraw-Hill Book Co., Inc., New. York.,,

7 Haszeldine et al.: Jour. Chem'.,SocL, 1953 page 159 2. V j Simons: Fluorine Chemistry, vol. II. page 412, 1954, I co I Academic Press Inc., New York. p

.- 10. The process of claim 7 accomplished under su- 

1. A FLUORINATED INTERNAL OLEFIN OF THE GROUP CONSISTING OF H(CF2)ICF=CFCYF2Y+1 AND
 7. THE PROCESS WHICH COMPRISES HEATING A FLUOROACYL HALIDE OF THE FORMULA 